Security methods based on memory data encoded into magnetic cards such as personal identification numbers or passwords are widely used in today's business, industrial, and governmental communities. With the increase in electronic transactions and verification there has also been an increase in lost or stolen cards, and forgotten, shared, or observed identification numbers or passwords. Because the magnetic cards offer little security against fraud or theft there has been a movement towards developing more secure methods of automated recognition based on unique, externally detectable, personal physical anatomic characteristics such as fingerprints, iris pigment pattern and retina prints, or external behavior characteristics; for example, writing style and voice patterns. Known as biometrics, such techniques are effective in increasing the reliability of recognition systems by identifying a person by characteristics that are unique to that individual. Some representative techniques include fingerprint recognition focusing on external personal skin patterns, hand geometry concentrating on personal hand shape and dimensions, retina scanning defining a person's unique blood vessel arrangement in the retina of the eye, voice verification distinguishing an individual's distinct sound waves, and signature verification.
Biometric applications may include but are not limited to, for instance physical access to restricted areas or applications; and access to computer systems containing sensitive information used by the military services, intelligence agencies, and other security-critical Federal organizations. Also, there are law enforcement applications which include home incarceration, parole programs, and physical access into jails or prisons. Also, government sponsored entitlement programs that rely on the Automated Fingerprint Identification System(AFIS) for access are important to deter fraud in social service programs by reducing duplicate benefits or even continued benefits after a recipient's demise.
Biometric recognition can be used in “identification mode”, where the biometric system identifies a person from the entire enrolled population by searching a database for a match. A system can also be used in “verification mode”, where the biometric system authenticates a person's claimed identity from his/her previously enrolled pattern of biometric data. In many biometric applications there is little margin for any inaccuracy n either the identification mode or the verification mode.
Current commercially available biometric methods and systems are limited because they use only externally visible distinguishing characteristics for identification; for example, fingerprints, iris patterns, hand geometry and blood vessel patterns. To date, the most widely used method is fingerprinting but there are several problems which have been encountered including false negative identifications due to dirt, moisture and grease on the print being scanned. Additionally, some individuals have insufficient detail of the ridge pattern on their prong due to trauma or a wearing down of the ridge structure. More important, some individuals are reluctant to have their fingerprint patterns memorialized because of the ever increasing accessibility to personal information.
Other techniques, currently in use are iris pigment patterns and retina scanning. These methods are being introduced in many bank systems, but not without controversy. There are health concerns that subjecting eyes to electromagnetic radiation may be harmful and could present unidentified risks.
Another limitation of current biometric systems, is the relative ease with which external physical features can be photographed, copied or lifted. This easy copying of external characteristics lends itself quite readily to unauthorized duplication of fingerprints, eye scans, and other biometric patterns. With the advancement of cameras, videos, lasers and synthetic polymers there is technology available to reproduce a human body part with the requisite unique physical patterns and traits of a particular individual. In high level security systems, where presentation of a unique skin or body pattern needs to be verified for entry, a counterfeit model could be produced, thereby allowing unauthorized entry into a secured facility by an imposter. As these capabilities evolve and expand there is a greater need to verify whether the body part offered for identification purposes is a counterfeit reproduction or the severed or lifeless body part of an authorized individual.
U.S. Pat. No. 5,719,950 (Osten), incorporated by reference herein, suggests that verifying an exterior specific characteristic of an individual such as fingerprint in correlation with a non-specific characteristic such as oxygen level in the blood can determine if the person seeking authentication is actually present. This method may be effective but still relies on exterior characteristics for verification of the individual. Also, the instrumentation is complicated having dual operations which introduce more variables to be checked before identity is verified.
Current biometric systems are also limited in size. For example, a fingerprint scanner must be at least as big as the fingerprint it is scanning. Other limitations include the lack of moldability and flexibility of some systems which prevents incorporation into flexible and moving objects. Finally, the complex scanning systems in current biometric methods are expensive and this high cost prevents the widespread use of these systems in all manner of keyless entry applications.
Accordingly, there is a need for more compact, moldable, flexible, economical and reliable automated biometric recognition methods and systems which use non-visible physical characteristics which are not easily copied, photographed, or duplicated. This would eliminate concerns regarding fingerprints that are unidentifiable due to dirt, grease, moisture or external surface deterioration; potential risks involved in eye scanning; costly instrumentation that depends on external characteristics, and the possibility of deceiving a system with an artificial reproduction of a unique external characteristic used for identification.